Table 3. Demographic and clinical characteristics of the recruited subjects classified by serum IgE levels.
| Characteristics | High-IgE group | Low-IgE group | Healthy group | P value |
|---|---|---|---|---|
| Sample (%) | 21 (47.7) | 8 (18.2) | 15 (34.1) | – |
| Female (%) | 14 (66.7) | 3 (37.5) | 8 (53.3) | 0.218 |
| BMI (kg/m2) | 23.3±0.5 | 24.3±0.8 | 22.5±1.1 | 0.202 |
| Asthma duration (years) | 9.5 (5.1, 13.8) | 12.8 (3.3, 22.2) | – | 0.518 |
| Acute attacks (times/years) | 1.1 (0.5, 1.7) | 0 | – | 0.005& |
| Nasal disease duration (years) | 9.3 (5,13.6) | 8.9 (0.1, 17.6) | – | 0.549 |
| OCS (sample size, %) | 7 (33.3) | 0 (0) | – | 0.142 |
| $ICS | 3.2 (2.5, 3.4) | 2.9 (2.8, 3.1) | – | 0.401 |
| Sputum eosinophils (%) | 23.8±4.5 | 11.2±6.3 | 1.2±0.5 | <0.001* |
| Sputum neutrophils (%) | 53.4±4.9 | 36.4±11 | 55.9±8.9 | 0.305 |
| ACT score | 22.7±0.3 | 23.1±0.2 | – | 0.684 |
| FVC%-predicted (%) | 88.1±4 | 92±4.1 | 96.8±2.8 | 0.400 |
| FEV1%-predicted (%) | 72±5 | 72±5.3 | 95.9±2.9 | 0.004*# |
| FEV1/FVC ratio | 66.4±2.5 | 65.3±4.1 | 84.3±2.3 | <0.001*# |
| PEF%-predicted (%) | 75.6±5.5 | 83.2±9 | 96.8±5.8 | 0.09 |
| FEF25-75%-predicted (%) | 36±4.6 | 35±5.4 | 79.7±5.8 | <0.001*# |
| MEF75%-predicted (%) | 55±7.1 | 43±8 | 85±9.3 | 0.010# |
| MEF50%-predicted (%) | 39.4±5.1 | 41.1±7.4 | 80.4±6 | <0.001*# |
| MEF25%-predicted (%) | 36±4.3 | 30.5±3.8 | 75.4±4 | <0.001*# |
| Blood eosinophils (%) | 5.6±0.8 | 3.3±0.4 | 1.3±0.2 | <0.001* |
| $Total IgE (IU/mL) | 2.4 (2.3, 2.7) | 1.6 (1, 1.8) | 1.3 (0.9, 1.5) | <0.001*& |
*, high-IgE asthma (HEA) group vs. healthy group; #, low-IgE asthma (LEA) group vs. healthy group; &, HEA group vs. LEA group, Inhaled corticosteroid (ICS) was normalized to budesonide; $, logarithmic transformation was used because ICS dose and serum Total IgE data presented skewed distribution. Data expressed as mean ± standard deviation, or median (interquartile range), or percentage (%). P values were determined using t test, Mann-Whitney U test, or chi-square test among two groups and by using LSD, Bonferroni, and Kruskal-Wallis tests among three groups. ICS, inhale corticosteroid, OCS, oral corticosteroid, BMI, body mass index, FVC%-pred, forced vital capacity per predicted, FEV1%-predicted: Forced expired volume in one second per predicted, FEV1/FVC ratio, forced expiratory volume in one second to forced vital capacity ratio, PEF%-predicted, peak expiratory flow rate per predicted, FEF25–75%-predicted, force expiratory flow from 25–75% of FVC per predicted, MEF75%-predicted, maximal expiratory flow after 75% of the FVC per predicted, MEF50%-predicted, maximal expiratory flow after 50% of the FVC per predicted, MEF25%-predicted, maximal expiratory flow after 25% of the FVC per predicted.